JSC2012-E-238166 (16 Nov. 2012) --- NASA astronaut Chris Cassidy, Expedition 35/36 flight engineer, attired in a training version of his Extravehicular Mobility Unit (EMU) spacesuit, is submerged in the waters of the Neutral Buoyancy Laboratory (NBL) near NASA's Johnson Space Center. Divers (out of frame) are in the water to assist Cassidy in his rehearsal, which is intended to help prepare him for work on the exterior of the International Space Station. Photo credit: NASA